Discontinuous reception method, mobile station, base station and wireless communication system

ABSTRACT

A discontinuous reception method, mobile station, base station and wireless communication system are provided in the present invention. The discontinuous reception method in the wireless communication system includes the following steps: in case of a continuous carrier aggregation, setting a common On Duration timer and/or a common Discontinuous Reception inactivity timer for a primary cell and each secondary cell; and in case of a discontinuous carrier aggregation, setting an independent On Duration timers and/or an independent Discontinuous Reception inactivity timers for the primary cell and each secondary cells. The present invention realizes discontinuous reception of the carrier aggregation, thus saving power consumption of the mobile station.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of U.S. patent application Ser. No. 13/820,640,filed Mar. 4, 2013, which is a National Stage Application of PCTApplication No. PCT/CN2011/075507, filed Jun. 9, 2011, which claimspriority to Chinese Patent Application No. 2010 10 506 073.X, filed Sep.30, 2010. The entire contents of U.S. patent application Ser. No.13/820,640 is incorporated herein by reference.

FIELD

The invention relates to discontinuous reception in wirelesscommunication system, and particularly to the discontinuous receptionunder carrier aggregation (CA).

BACKGROUND

The future LTE-A (Long Term Evolution Advanced) system will support atransmission bandwidth up to 100 MHz, while the maximum transmissionbandwidth supportable by the LTE (Long Term Evolution) standard is 20MHz. Thus to achieve the higher transmission bandwidth, it requires toaggregate multiple carriers. Carrier aggregation (CA) is a technique ofaggregating multiple carriers for combined transmission, which isproposed by 3GPP (3rd Generation Partnership Project) to meet the hightransmission bandwidth requirement of the future mobile systems. Carrieraggregation may be classified into consecutive carrier aggregation andnon-consecutive aggregation based on the positions of the carriers thatare aggregated on the spectrum. LTE-A will support both of the two CAscenarios. While introducing the CA technique, 3GPP also considers itsbackward compatibility, which means that user equipments (UEs)supporting CA and UEs not supporting CA will co-exist for a long time inthe future. A CA supporting UE can be connected to a plurality ofcomponent carriers (CCs) at the same time, and a UE not supporting CAcan be connected to only a certain CC.

With the introduction of the CA technique, each cell may be configuredwith a plurality of CCs and a UE may also use multiple of CCs. Not allthe UEs use all the CCs of the corresponding cell. Those CCs used by theUE are referred to as configured CCs and those not in use are called asnon-configured CC. The so called configured/non-configured is definedwith respect to each UE. That is, different UEs may have differentconfigured/non-configured CCs

The configured CCs may be further classified as activated CC anddeactivated CC. The UE transmits data over the activated CC. No datatransmission is performed over the deactivated CC. The deactivated CCdoes not support difficult measurements such as CQI (Channel QualityIndicator).

The advantage of introducing activated/deactivated CC lies in that, theCCs that are not in use temporarily can be set in the deactivated stateso that the power of the UE may be saved. The deactivated CC may beswitched into the activated state rapidly via MAC signaling, and unlikethe non-configured CC, the deactivated CC can perform measurementthereon and the measurement information of the deactivated CC can beused by the base station to set related parameters. In this way, therequirements of the burst data services can be better met.

In LTE-A, each cell has a plurality of CCs and each UE can be allocatedwith a plurality of CCs. LTE-A defines the concept of “special cell”.Each UE has only one special cell and the special cells of different UEsmay be different from each other. Over the special cell, the systemprovides security input function and NAS (non-access) layer informationto the UE. From the view point of the system, each CC is equivalent to acell, and is allocated with globally unique cell identification. Fromthe view point of the UE, even if the UE is allocated with a pluralityof CCs, it can only see one cell, i.e. the special cell, while the otherCCs are used as uplink and downlink resources.

LTE-A introduces the concept of PCC (primary component carrier). Each UEis configured with an uplink PCC and a downlink PCC. The uplink controlinformation is transmitted over the uplink PCC. The radios link failure(RLF) information is monitored over only the primary cell (Pcell). Thecell corresponding to the PCC is thus called as primary cell (Pcell),and the other cells are called as secondary cell (Scell). Pcell is thespecial cell.

To save the power of the mobile station, LTE Rel-8 introduces theconcept of DRX (Discontinuous Reception) such that the listening ofPDCCH (Physical Downlink Control Channel) is stopped when there is nodata transmission over the air interface, thereby reducing the operationof the receiver, decreasing the power consumption of the mobile stationand lengthening the life of the battery.

Some concepts of DRX in LTE Rel-8 are explained blow.

1. On Duration time: a UE wakes from dormant state and goes into the onduration, and starts an on duration timer. During the on duration, theUE receives the information of PDCCH. On PDCCH, there is signalinginformation related to the UE which is transmitted from the network sideto the UE, such as control information of resource allocation, such asconfirmation, power control, resource allocation and reallocation, etc.If the UE can successfully decode the information of the PDCCH signalindicating the initial uplink or downlink user data transmission, itstarts a discontinuous reception inactivity timer and goes into theinactivity time; otherwise, the UE goes into the dormant state after theon duration time ends (i.e. expire of the on duration timer)

2. Inactivity time: after the UE successfully decodes the PDCCH channel,the UE starts the DRX inactivity timer and goes into the inactivitytime. During the inactivity time, the UE continues listening to thePDCCH and related control channels. If the UE successfully decodes thePDCCH and related control channels before the expire of the DRXinactivity timer, the UE restarts the DRX inactivity timer and onceagain goes into the inactivity time; otherwise, the UE goes into thedormant time after the expire of the DRX inactivity timer, and proceedsto the next DRX cycle.

3. Active time: during the active time, the UE monitors the PDCCHchannel; the on duration time and the inactivity time both belongs tothe active time.

4. Dormant time: the UE is in an off state during the dormant time.

5. HARQ RTT Timer (Hybrid Automatic Retransmission Request Round-TripTime): this timer is used for the timing of the least time intervalpredicted to be used for downlink retransmission of the UE. When a newdownlink data transmission is detected, the HARQ RTT Timer is started,and if the received data is correctly decoded upon the expiring of theHARQ RTT Timer, the UE goes into the dormant time and proceeds to thenext DRX cycle.

6. DRX retransmission timer: this timer is used for the timing of thetime predicted to be needed for downlink retransmission for the UE. Whenthe HARQ RTT Timer expires and there exists data that has not beensuccessfully decoded in the corresponding HARQ buffer, the DRXretransmission timer is started, and this time the PDCCH is listened to.

7. Contention Resolution: once the uplink message contains C-RNTI (CellRadio Network Temporary Identifier which is allocated by wirelessnetwork controller) MAC control element or the uplink message containsCCCH SDU (Common Control Channel Service (CCCH) Data Unit (SDU)), the UEstarts a contention resolution timer and monitors the PDCCH until thecontention resolution timer expires. When receiving the massageindicating the successful contention resolution, the contentionresolution timer is stopped.

8. DRX short cycle timer: when the DRX inactivity timer expires, the DRXshort cycle timer is started. If the DRX short cycle timer expires, along cycle DRX is started. The UE can be configured as short DRX cycleand long DRX cycle. The short DRX cycle is optional. In the case thatthe short DRX cycle is configured, after entering into the short DRXcycle state, the UE goes into the long DRX cycle if it does not listenedits own PDCCH packet after the DRX short cycle timer expires. If theshort DRX cycle is not configured, the UE directly goes into the longDRX cycle.

If a DRX MAC (Media Access Control) control information unit isreceived, it means that the base station requires the UE to go into thedormant state. At this time, the on duration timer and the DRXinactivity timer are stopped, but the time related to the retransmissionis not stopped.

With the introduction of CA, a mobile station can simultaneously use aplurality of CCs, which makes the DRX operation environment morecomplex. In addition, under CA scenarios, the mobile station and theprotocol design face the huge challenge of high power consumption. Howto make the DRX, which is an important means for saving the power of themobile station, effectively work under CA scenarios is another issue tobe solved.

SUMMARY

The following presents a simplified summary of the invention in order toprovide a basic understanding of some aspects of the invention. Thissummary is not an exhaustive overview of the disclosure. It is notintended to identify key or critical elements of the disclosure or todelineate the scope of the disclosure. Its sole purpose is to presentsome concepts in a simplified form as a prelude to the more detaileddescription that is discussed later.

The invention is directed to solve the above technical problem.

According to an aspect of the invention, there is provided adiscontinuous reception method in a wireless communication systemincluding determining to employ a consecutive carrier aggregation or anon-consecutive carrier aggregation; in case of the consecutive carrieraggregation, for a primary cell and each of the secondary cells, settinga common on-duration timer (on Duration Timer) and/or a commondiscontinuous reception inactivity timer (DRX inactivity timer); and incase of the non-consecutive carrier aggregation, for a primary cell andeach of the secondary cells, setting separate on-duration timers and/orseparate discontinuous reception inactivity timers.

According to another aspect of the invention, there is provided adiscontinuous reception method in wireless communication system, carrieractivating/deactivating operation separate from the carrierconfiguration process is used in the wireless communication system, andthe method includes: for a primary cell and each of secondary cells,setting a common on-duration timer and/or discontinuous receptioninactivity timer.

According to another aspect of the invention, there is provided a mobilestation including a determining unit configured to determine to employ aconsecutive carrier aggregation or a non-consecutive carrieraggregation; and

a setting unit configured to, in case of the consecutive carrieraggregation, set a common on-duration timer and/or a commondiscontinuous reception inactivity timer for a primary cell and each ofsecondary cells; and in case of the non-consecutive carrier aggregation,set separate on-duration timers and/or separate discontinuous receptioninactivity timers for the primary cell and each of the secondary cells.

According to another aspect of the invention, there is provided a mobilestation including an activating/deactivating unit configured to performcarrier activating/deactivating operation separate from the carrierconfiguration process; and a setting unit configured to set a commonon-duration timer and/or discontinuous reception inactivity timer for aprimary cell and each of the secondary cells.

According to another aspect of the invention, there is provided a basestation including a transmitting unit for sending an instruction to themobile station to control the mobile station to perform the methodmentioned above.

According to another aspect of the invention, there is provided awireless communication system including the above mobile station and theabove base station.

In addition, an embodiment of the invention provides computer programfor realizing the above methods.

Furthermore, an embodiment of the invention provides a computer programproduct in the form of computer readable medium on which there arerecorded computer program codes for the above methods.

The invention realizes the discontinuous reception under CA, therebysaving the power of the mobile station.

The above and other advantages of the disclosure can be more apparentwith reference to the best mode of the invention in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

The above and other objects, features and advantages of the embodimentsof the disclosure can be better understood with reference to thedescription given below in conjunction with the accompanying drawings,throughout which identical or like components are denoted by identicalor like reference signs.

FIG. 1 is a schematic diagram showing a first CA scenario according tothe related art;

FIG. 2 is a schematic diagram showing a second CA scenario according tothe related art;

FIG. 3 is a schematic diagram showing a third CA scenario according tothe related art;

FIG. 4 is a schematic flow chart showing a discontinuous receptionmethod in a wireless communication system according to an embodiment ofthe invention;

FIG. 5 is a schematic flow chart showing a discontinuous receptionmethod in a wireless communication system according to anotherembodiment of the invention;

FIG. 6 is a schematic block diagram showing a mobile station accordingto an embodiment of the invention;

FIG. 7 is a schematic block diagram showing a mobile station accordingto an embodiment of the invention;

FIG. 8 is a schematic block diagram showing a base station according toan embodiment of the invention;

FIG. 9 is a schematic block diagram showing a wireless communicationsystem according to an embodiment of the invention; and

FIG. 10 is a schematic block diagram showing the structure of a computerrealizing embodiments of the invention.

DETAILED DESCRIPTION

Some embodiments of the present disclosure will be described inconjunction with the accompanying drawings hereinafter. It should benoted that the elements and/or features shown in a drawing or disclosedin an embodiments may be combined with the elements and/or featuresshown in one or more other drawing or embodiments. It should be furthernoted that some details regarding some components and/or processesirrelevant to the disclosure or well known in the art are omitted forthe sake of clarity and conciseness.

FIGS. 1, 2, and 3 illustrate application scenarios of the presentapplication. The 3 application scenarios as shown are preferreddeployment scenarios for carrier aggregation and represent 3 typicalapplication examples of carrier aggregation. In FIG. 1 the coveragescopes of the cells corresponding to carriers F1 and F2 aresubstantially coincident, i.e. F1 and F2 provide coverage areas similarto each other. F1 and F2 may be arranged in the same carrier band, whichis a typical consecutive CA scenario. FIGS. 2 and 3 each show an exampleof non-consecutive CA, in which F1 and F2 may be located in differentcarrier band. The cell corresponding to F1 is used to ensure thecoverage and the cell corresponding to F2 is used to improve thethroughput. The difference between FIG. 2 and FIG. 3 lies in that, inFIG. 3 the antenna of the cell corresponding to F2 is directed to theedge area of the cell corresponding to F1, therefore the applicationscenario of FIG. 3 can significantly improve the throughput of the edgearea of the cell corresponding to F1.

FIG. 4 is a schematic flow chart showing a discontinuous receptionmethod in a wireless communication system according to an embodiment ofthe invention. The wireless communication system is a CA supportingsystem. CA can be classified as consecutive CA and non-consecutive CAbased on the positions of the aggregated carriers on the spectrum. Inconsecutive CA, the aggregated CCs are consecutive on the spectrum. Innon-consecutive CA, the aggregated CCs are not consecutive on thespectrum.

In step 402, it is determined whether to use the consecutive CA or thenon-consecutive CA. In the case of consecutive CA, the processingproceeds to step 404. In the case of non-consecutive CA, the processingproceeds to step 406. In step 404, for the primary cell and eachsecondary cell, the common on duration timer and/or DRX inactivity timerare set. In step 406, for the primary cell and each secondary cell,separated on Duration Timers and/or separated DRX inactivity timers areset.

In an example, in step 402, whether the mobile station uses consecutiveCA or non-consecutive CA may be determined based on signaling from thebase station. In steps 404 and 406, the timers can be set based onsignaling from the base station.

For consecutive CA, since the aggregated carriers are in the same band,their coverage scopes are substantially the same. Thus, the common onduration timer and/or DRX inactivity timer may be set for the primarycell and each secondary cell. For non-consecutive CA, since theaggregated carriers are in different bands, their propagationcharacteristics are different from each other. Thus, separated onduration timer and/or separated DRX inactivity timer may be set for theprimary cell and each secondary cell.

The DRX on Pcell and DRX on Scell are explained separately below.

I, DRX on Pcell

In the following description, those same with the related art (e.g. LTERel-8 standard) are omitted, and only the differences over the relatedart are described. The DRX operations and the DRX parameterconfigurations are described below respectively.

1. DRX Operations

In an example, under CA scenario, since there exists cross-scheduling(i.e. the PDCCH of a cell may be used to indicate the data transmissionPDCCH of the other cells), if an indication is received over the PDCCHof Pcell indicating new data transmission over other Scells, the timeron the Pcell needs to be started or reset. For example, if the Pcellreceives a downlink transmission allocation indicator or uplinktransmission authorization containing a Carrier indicator field (CIF),the DRX inactivity timer on Pcell is started or reset, and optionallythe Scell corresponding to the CIF may be notified to start or reset itsDRX inactivity timer. If PDCCH of the Pcell receives a downlinktransmission allocation indicator or uplink transmission authorizationexcluding a Carrier indicator field (CIF), only the timer on the Pcellis started or reset.

In an example, when processing the contention resolution timer, if themessage indicating successful contention resolution is received on onlythe Pcell, separated contention resolution timers may be set for thePCell and each Scell. Otherwise, a common contention resolution timermay be set for the PCell and each Scell. In an example, if in thewireless communication system the message indicating successfulcontention resolution is received on only the Pcell, the contentionresolution timer of the Pcell is stopped upon receipt of the messageindicating successful contention resolution. At this time, thecontention resolution timer of the Scell is not affected. As long as thetimer on the Pcell does not expire, the PDCCH on the Pcell is monitored.In an example, if wireless communication system does not require thecontention resolution message (For example, the contention resolutionmessage for a contention-based random access process (Msg4) to betransmitted over only the Pcell, the contention resolution timer of theScell is also started when the contention resolution timer of the Pcellis started; When the message indicating successful contention resolutionis received on the Pcell or any Scell, the contention resolution timersof the Pcell and Scell are stopped. For example, when the Pcell startsits contention resolution timer (Pcell starts first), a message is sentto the Scells indicating to start the corresponding contentionresolution timers. Upon receiving the message, each Scell starts itscontention resolution timer. When the message indicating successfulcontention resolution is received on the Pcell or any Scell, thecontention resolution timer of the cell is stopped, and the celltransmits a message to other cells indicating to stop the correspondingcontention resolution timers.

In CA scenario, when processing the DRX retransmission timer, it isconsidered that each CC corresponds to a separate HARQ entity, and theretransmission on the Pcell does not cause the Scell to listen to thePDCCH. Thus, the operations on the DRX retransmission timer of the Pcelldo not affect the operations of the DRX retransmission timer on theScell. The operations of the DRX retransmission timers between theScells are separate from each other. The start or expiring of the DRXretransmission timer of a Scell does not affect the operations of theDRX retransmission timer of another Scell. Separate DRX retransmissiontimers may be set for each of the Pcell and Scells.

With respect to the processing of the DRX short cycle timer, since thePcell is very important in CA and the data transmission thereupon may befrequent, inappropriate configuration of the DRX short cycle timer maycause the mobile station to inappropriately go into long cycle DRX,which may bring about data loss or affect the quality of service. Inview of this, in an example, for the DRX on the Pcell, the mobilestation does not go into the long cycle DRX even if the DRX short cycletimer expires.

2. DRX Parameter Configurations

DRX parameter configurations are described. The parts that are the samewith LTE Rel-8 in the related art are omitted.

In an example, in the case of consecutive CA, the DRX parameters of theprimary cell and each secondary cell may be set as the same values. Itis to be noted that the expression “set as the same values” means thatthe same parameters, which the primary cell and each secondary cell eachhave, are set as the same values. In some cases, for example, theprimary cell may have not a parameter, e.g. Long DRX cycle, while thesecondary cell may have this parameter. The interpretation may also beapplied to the following description. In the case of non-consecutive CA,the DRX parameters of the primary cell and each secondary cell may beset as different values.

DRX inactivity timer: in an example, the parameter may be adjusteddynamically according to one or more conditions of the data amount to betransmitted by the mobile station, the position of the mobile station,the moving velocity, the signal quality and the coverage scope of thePcell and the like. The parameter may be set as relatively small in atleast one of the following cases: the data amount to be transmitted bythe mobile station is small, the mobile station is relatively near tothe base station, the signal quality is relatively good, and the movingvelocity is relatively small with respect to the coverage. Otherwise,the parameter may be set as relatively large.

DRX short cycle timer: in an example, the value may be set regardless ofthe DRX performance of the Pcell since the Pcell does not contain longcycle DRX.

Long DRX cycle: in an example, the value may be not set since the Pcelldoes not contain long cycle DRX.

On Duration Timer: in an example, the parameter may be adjusteddynamically according to one or more conditions of the data amount to betransmitted by the mobile station, the position of the mobile station,the moving velocity, the signal quality and the coverage scope of thePcell and the like. The parameter may be set as relatively small in atleast one of the following cases: the data amount to be transmitted bythe mobile station is small, the mobile station is relatively near tothe base station, the signal quality is relatively good, and the movingvelocity is relatively small with respect to the coverage. Otherwise,the parameter may be set as relatively large.

DRX cycle: in an example, the parameter may be adjusted dynamicallyaccording to one or more conditions of the data amount to be transmittedby the mobile station, the position of the mobile station, the movingvelocity, the signal quality and the coverage scope of the Pcell and thelike. The parameter may be set as relatively small in at least one ofthe following cases: the data amount to be transmitted by the mobilestation is small, the mobile station is relatively near to the basestation, the signal quality is relatively good, and the moving velocityis relatively small with respect to the coverage. Otherwise, theparameter may be set as relatively large.

CQI/PMI/RI (Channel Quality Indicator/Pre-coding Matrix Index/RateIndicator) reports: in existed LTE Rel-8, the time periods fortransmitting these feedback reports may be configured, for example theymay be transmitted during the active time or the on duration time. Theperformance of the Pcell significantly affects the overall performanceof CA, thus obtaining the feedback reports in time is very important. Inan example of the embodiment, in the Pcell, these feedback reports areperiodically sent as long as the mobile station is in the active time.

II, DRX on Scell

In the following description, those same with the related art (e.g. LTERel-8 standard) are omitted, and only the differences over the relatedart are described. The DRX operations and the DRX parameterconfigurations are described below respectively. The DRX operations oneach Scell may be performed independently, and the DRX parameters of theScells may be the same or be different from each other as required inthe different scenarios.

1. DRX Operations

In an example, in CA scenario, in the case of cross-scheduling, if aScell does not configure PDCCH, there is not DRX on this Scell, that is,DRX configuration is not performed on this Scell.

In an example, after the Scell receives a downlink transmissionallocation indication or uplink transmission authorization containing acarrier indicator field (CIF), the DRX inactivity timer of the Scell isstarted or reset, and optionally the Scell may notify the other cellcorresponding to the CIF to start or reset its DRX inactivity timer. Ifthe Scell receives a downlink transmission allocation indication oruplink transmission authorization not containing a carrier indicatorfield (CIF), only the DRX inactivity timer of this Scell is started orreset.

In an example, in CA scenario, if a Scell receives a start contentionresolution timer message from the Pcell, this timer is start, and thePDCCH over the Scell is monitored. When receiving a stop contentionresolution timer message from the Pcell or the other Scell, the Scellstops its contention resolution timer. If the Scell receives a messageindicating successful contention resolution, it stops its contentionresolution timer, and notifies the Pcell and the other Scells to stoptheir corresponding contention resolution timers.

In an example, the processing of the DRX retransmission timers betweenScells may be independent with each other.

2. DRX Parameter Configurations

DRX parameter configurations are described below. The parts that are thesame with the existed LTE Rel-8 are omitted. DRX parameters may includethe expiring times of the timers, such as DRX inactivity timer, DRXshort cycle timer, and on duration timer, in the DRX; the time length ofthe DRX cycle and the cycle of transmitting the feedback reports. In thefollowing, the expiring time of a timer is also simplified as thistimer.

In an example, the parameters of the Pcell and each Scell can be thesame or different from each other as required by the differentscenarios. The policies of parameter configurations under differentscenarios are described below.

If the mobile station is under the consecutive CA scenario, as shown inFIG. 1, since the position of the mobile station is determined and thecoverage scopes of the carriers are the same, the relative signalquality of the Pcell and Scells are the same, regardless of theirabsolute signal quality. Thus the DRX parameter configurations of thePcell and the Scells may be the same. That is, it is unnecessary to setdifferent values for the DRX parameters of the Pcell and the Scells.

In the case that the mobile station is in non-consecutive CA scenario,As shown in FIGS. 2 and 3, since the coverage scopes of the carriers aredifferent from each other, the mobile station is within the coverage ofthe good quality signal of the Pcell, but can not be ensured to bewithin the coverage of the good quality signal of the Scells. Therefore,the DRX parameter configurations between Scells and Pcell and betweenScells are preferred to be separate from each other. DRX parameters canbe configured separately according to the network deployment and theposition of the mobile station.

DRX inactivity timer: the parameter may be adjusted dynamicallyaccording to one or more conditions of the data amount to be transmittedby the mobile station, the position of the mobile station, the movingvelocity, the signal quality and the coverage scope of the Scell and thelike. The parameter may be set as relatively small in at least one ofthe following cases: the data amount to be transmitted by the mobilestation is small, the mobile station is relatively near to the basestation, the signal quality is relatively good, and the moving velocityis relatively small with respect to the coverage. Otherwise, theparameter may be set as relatively large.

DRX short cycle timer: the parameter may be adjusted dynamicallyaccording to one or more conditions of the data amount to be transmittedby the mobile station, the position of the mobile station, the movingvelocity, the signal quality and the coverage scope of the Scell and thelike. The parameter may be set as relatively small in at least one ofthe following cases: the data amount to be transmitted by the mobilestation is small, the mobile station is relatively near to the basestation, the signal quality is relatively good, and the moving velocityis relatively small with respect to the coverage. Otherwise, theparameter may be set as relatively large.

On Duration Timer: the parameter may be adjusted dynamically accordingto one or more conditions of the data amount to be transmitted by themobile station, the position of the mobile station, the moving velocity,the signal quality and the coverage scope of the Pcell and the like. Theparameter may be set as relatively small in at least one of thefollowing cases: the data amount to be transmitted by the mobile stationis small, the mobile station is relatively near to the base station, thesignal quality is relatively good, and the moving velocity is relativelysmall with respect to the coverage. Otherwise, the parameter may be setas relatively large.

DRX Cycle: the parameter may be adjusted dynamically according to one ormore conditions of the data amount to be transmitted by the mobilestation, the position of the mobile station, the moving velocity, thesignal quality and the coverage scope of the Pcell and the like. Theparameter may be set as relatively small in at least one of thefollowing cases: the data amount to be transmitted by the mobile stationis small, the mobile station is relatively near to the base station, thesignal quality is relatively good, and the moving velocity is relativelysmall with respect to the coverage. Otherwise, the parameter may be setas relatively large.

CQI/PMI/RI reports: in existed LTE Rel-8, the time periods fortransmitting these feedback reports may be configured, for example theymay be transmitted during the active time or the on duration time. Thesereports are very important for canceling the Scell that cannot meet thetransmission quality requirements and thus may be dynamically adjustedbased on the signal qualities of the Scells. In an example, if thesignal qualities of the Scells are low, these feedback reports areperiodically sent in the active time; otherwise, these reports areperiodically sent only in the on-duration time

FIG. 5 is a schematic flow chart showing a discontinuous receptionmethod in a wireless communication system according to anotherembodiment. The wireless communication system is a CA supporting system.In the wireless communication system, the activating/deactivatingoperations are separate with the carrier configuration processes.

FIG. 5 involves step 502. In step 502, for the primary cell and eachsecondary cell, a common on Duration timer and/or a common DRXinactivity timer are set.

When a carrier is not in use at a certain time, it can be activatedoptionally, rather than being set into the non-configured state. In thisway, when the carrier needs to be reused, it can be simply reactivatedwithout the need of reconfiguring it. This can not only save thesignaling overhead due to the frequent reconfiguration, but alsoflexibly select the carrier to be activated, thereby further reducingthe power consumption of the mobile station. In combination with theactivating/deactivating commands, the DRX complexity under CA can bereduced. In the wireless communication system utilizing carrieractivating/deactivating operations that are separate from the carrierconfiguration process, a common on Duration timer and/or a common DRXinactivity timer may be set for the primary cell and each secondarycell.

In an example, if the message indicating the successful contentionresolution is received on only the Pcell, separate contention resolutiontimers may be set for the primary cell and each secondary cell,otherwise, a common contention resolution timer may be set for theprimary cell and each secondary cell.

In an example, separate DRX retransmission timers may be set for theprimary cell and each secondary cell.

In an example, DRX parameters of the primary cell and each secondarycell configurations.

In an example, if it is determined that a cell or some cells are notneeded based on the data amount to be transmitted, the position of themobile station, the moving velocity, the signal quality and the carriercoverage and the like, the cell or cells are deactivated and the DRXprocesses on the cell or cells are accordingly terminated, and at thistime, the PDCCH corresponding to the cell or cells need not bemonitored. If a cell or cells need to be reactivated as required, it isjudged, based on the DRX running rules, whether the PDCCH correspondingto the cell or cells need to be monitored, and when it is judged thatthe PDCCH corresponding to the cell or cells need to be monitored, thePDCCH corresponding to the cell or cells is monitored.

It is to be noted that the embodiment shown in FIG. 4 may also beapplied to the wireless communication system utilizing DRX withactivating/deactivating processes.

FIG. 6 is a schematic block diagram showing a mobile station 600according to an embodiment of the invention. The mobile station 600includes a determining unit 602 configured to determine whether toemploy consecutive CA or non-consecutive CA; and a setting unit 604configured to: in case of the consecutive carrier aggregation, set acommon on-duration timer and/or a common discontinuous receptioninactivity timer for a primary cell and each of secondary cells; and incase of the non-consecutive carrier aggregation, set separateon-duration timers and/or separate discontinuous reception inactivitytimers for the primary cell and each of the secondary cells.

In an example, the mobile station 600 further includes a receiving unit(not shown). When the receiving unit receives, over the PDCCH of Pcell,an indication indicating new data transmission over other Scells, thesetting unit 604 starts or resets the DRX inactivity timer of the Pcell.

In an example, if the receiving unit receives, over the Pcell or Scell,a downlink transmission allocation indicator or uplink transmissionauthorization containing a Carrier indicator field (CIF), the settingunit 604 starts or resets the DRX inactivity timer of the Pcell orScell, and starts or resets the DRX inactivity timer of the Scellcorresponding to the CIF. When the receiving unit receives, over thePcell or Scell, a downlink transmission allocation indicator or uplinktransmission authorization excluding a Carrier indicator field (CIF),the setting unit 604 starts or resets only the DRX inactivity timer ofthe Pcell or Scell.

In an example, the mobile station 600 further includes a receiving unit(not shown). If the receiving unit receives the message indicating thesuccessful contention resolution only over the Pcell, the setting unit604 sets separate contention resolution timers for the Pcell and eachScell. Otherwise, the setting unit 604 sets a common contentionresolution timer for the Pcell and each Scell.

In an example, the mobile station 600 further includes a receiving unit(not shown). If the message indicative of the successful contentionresolution is received only over the Pcell by the receiving unit, thesetting unit 604 stops the contention resolution timer of the Pcell whenthe message indicative of the successful contention resolution isreceived by the receiving unit. If the message indicative of thesuccessful contention resolution is not only received over the Pcell bythe receiving unit, when starting the contention resolution timer of thePcell, the setting unit 604 further starts the contention resolutiontimer of the Scell. The setting unit 604 stops the contention resolutiontimers of the Pcell and the Scell when the message indicative of thesuccessful contention resolution is received by the receiving unit overthe primary cell or over any of the secondary cells. Optionally, thesetting unit 604 sends a message of starting the contention resolutiontimer from the Pcell to the Scell, and when the Scell receives themessage of starting the contention resolution timer from the Pcell, thesetting unit 604 starts the contention resolution timer of the Scell.When the receiving unit receives the message indicating the successfulcontention resolution over the Pcell or any of the Scells, the settingunit 604 stops the contention resolution timer of the cell, and sends amessage of stopping the contention resolution timers to the other cells.The other cells stop their contention resolution timers upon receipt ofthe message.

In an example, the setting unit 604 sets separate discontinuousreception retransmission timers for the Pcell and each Scell.

In an example, the setting unit 604, in case of the consecutive carrieraggregation, sets the same value for DRX parameters of the Pcell andeach of Scells; and in case of the non-consecutive carrier aggregation,sets different values for DRX parameters of the Pcell and each of theScells.

In an example, the setting unit 604 still causes the mobile station togo into the short cycle DRX state in the case the DRX short cycle timerof the Pcell expires.

In an example, in case of at least one of the following: the data to betransmitted being of smaller amount, being closer to the base station,having better signal quality, and the moving speed of the mobile stationbeing smaller with respect to the converge area of the cell, the settingunit 604 sets a smaller expiring time value of DRX inactivity timer forthe cell and/or a smaller expiring time value of on-duration timer forthe cell, and/or sets a bigger DRX cycle for the cell.

In an example, the setting unit 604 sets the expiring time value of theDRX short cycle timer for the Pcell, regardless of the discontinuousreception performance of the Pcell.

In an example, the setting unit 604 does not set the DRX long cycletimer for the Pcell.

In an example, the mobile station further includes a feedback reporttransmitting unit (not shown) configured to send periodically feedbackreports for the Pcell during the active time.

In an example, the mobile station further includes a feedback reporttransmitting unit (not shown), wherein in case that the Scell has poorsignal quality, the feedback report transmitting unit sends periodicallya feedback report for the Scell during active time, otherwise thefeedback report transmitting unit sends the feedback report for theScell only during the on-duration time.

In an example, the setting unit 604 does not perform DRX configurationfor the Scell which has no configured PDCCH.

In an example, in case of at least one of following: the data to betransmitted being of smaller amount, being closer to the base station,having better signal quality, and the moving speed of the mobile stationis smaller with respect to the converge area of the cell, the settingunit 604 sets a smaller DRX short cycle timer for the Scell.

For the functions and operations of the components of the mobile station600, reference may be made to the embodiment shown in FIG. 4, thedescription of which is not repeated.

FIG. 7 is a schematic block diagram showing a mobile station TOOaccording to an embodiment of the invention. The mobile station 700includes an activating/deactivating unit 702 configured to performcarrier activating/deactivating operation separate from the carrierconfiguration process; and a setting unit 704 configured to set a commonon-duration timer and/or DRX inactivity timer for a Pcell and each ofthe Scells.

In an example, the mobile station 700 further includes a receiving unit(not shown). If the receiving unit receives the message indicating thesuccessful contention resolution only over the Pcell, the setting unit704 sets separate contention resolution timers for the Pcell and eachScell. Otherwise, the setting unit 704 sets a common contentionresolution timer for the Pcell and each Scell.

In an example, the setting unit 704 sets separate DRX retransmissiontimers for the Pcell and each Scell.

In an example, the setting unit 704 sets the same DRX parameter valuesfor the Pcell and each Scell.

In an example, the mobile station 700 further includes a receiving unit(not shown). After the activating/deactivating unit 702 deactivates acell, the receiving unit does not monitor the PDCCH corresponding to thecell and after the activating/deactivating unit 702 reactivates a cellthat has been deactivated, the setting unit 704 judges whether tomonitor the PDCCH corresponding to the cell based on the DRX runningrules. When the setting unit 704 judges that the PDCCH corresponding tothe cell needs to be monitored, the receiving unit monitors the PDCCHcorresponding to the cell.

In the above description, some embodiments of the invention aredescribed from the view point of the mobile station. Those skilled inthe art can appreciate, the steps in the method shown in the embodimentsdescribed with referenced to FIGS. 4-7 may be performed by the mobilestation under the control of the base station.

For the functions and operations of the components of the mobile station700, reference may be made to the embodiment shown in FIG. 5, thedescription of which is not repeated.

FIG. 8 is a schematic block diagram showing a base station 800 accordingto an embodiment of the invention. The base station 800 includes atransmitting unit 802 configured to send a command to the mobilestation, to control the mobile station to perform the method describedwith reference to FIG. 4 or 5.

FIG. 9 is a schematic block diagram showing a wireless communicationsystem 900 according to an embodiment of the invention. The wirelesscommunication system 900 includes the mobile station 902 described withreference to FIG. 6 or 7 and the base station 904 described withreference to FIG. 8.

Those skilled in the art can understand that the above embodiments andexamples are illustrative. The present disclosure should not be regardedas being limited to any particular embodiments or examples stated above.

In the disclosure, the expressions, such as “the first”, “the second”,and “the Nth” are used. Those skilled in the art will appreciate thatsuch expressions are used merely to differentiate the terms in literalso as to describe the invention clearly, and should not be considered asdefining the sequence or the like of the terms.

As an example, the component modules, units or steps in the aboveapparatuses and methods can be configured with software, hardware,firmware or any combination thereof in the base station (e.g. eNodeB) ormobile station node (e.g. the UE) of the communication system, as partof the physical layer apparatus of the base station or the mobilestation. The components, units or steps in the above apparatuses andmethods can be configured with software, hardware, firmware or anycombination thereof by using any appropriate means or manners known inthe art, the description of which is not detailed herein.

As can be understood, a system including the above apparatuses accordingto any of the above embodiments should also be encompassed in theprotection scope of the invention.

As an example, in the case of using software or firmware, programsconstituting the software for realizing the above method or apparatuscan be installed to a computer with a specialized hardware structure(e.g. the general purposed computer 1000 as shown in FIG. 10) from astorage medium or a network. The computer, when installed with variousprograms, is capable of carrying out various functions.

In FIG. 10, a central processing unit (CPU) 1001 executes various typesof processing in accordance with programs stored in a read-only memory(ROM) 1002, or programs loaded from a storage unit 1008 into a randomaccess memory (RAM) 1003. The RAM 1003 also stores the data required forthe CPU 1001 to execute various types of processing, as required. TheCPU 1001, the ROM 1002, and the RAM 1003 are connected to one anotherthrough a bus 1004. The bus 1004 is also connected to an input/outputinterface 1005.

The input/output interface 1005 is connected to an input unit 1006composed of a keyboard, a mouse, etc., an output unit 1007 composed of acathode ray tube or a liquid crystal display, a speaker, etc., thestorage unit 1008, which includes a hard disk, and a communication unit1009 composed of a modem, a terminal adapter, etc. The communicationunit 1009 performs communicating processing. A drive 1010 is connectedto the input/output interface 1005, if needed. In the drive 1010, forexample, removable media 1011 is loaded as a recording medium containinga program of the present invention. The program is read from theremovable media 1011 and is installed into the storage unit 1008, asrequired.

In the case of using software to realize the above consecutiveprocessing, the programs constituting the software may be installed froma network such as Internet or a storage medium such as the removablemedia 1011.

Those skilled in the art should understand the storage medium is notlimited to the removable media 1011, such as, a magnetic disk (includingflexible disc), an optical disc (including compact-disc ROM (CD-ROM) anddigital versatile disk (DVD)), an magneto-optical disc (including an MD(Mini-Disc) (registered trademark)), or a semiconductor memory, in whichthe program is recorded and which are distributed to deliver the programto the user aside from a main body of a device, or the ROM 1002 or thehard disc involved in the storage unit 1008, where the program isrecorded and which are previously mounted on the main body of the deviceand delivered to the user.

The present disclosure further provides a program product havingmachine-readable instruction codes which, when being executed, may carryout the methods according to the embodiments.

Accordingly, the storage medium for bearing the program product havingthe machine-readable instruction codes is also included in thedisclosure. The storage medium includes but not limited to a flexibledisk, an optical disc, a magneto-optical disc, a storage card, or amemory stick, or the like.

In the above description of the embodiments, features described or shownwith respect to one embodiment may be used in one or more otherembodiments in a similar or same manner, or may be combined with thefeatures of the other embodiments, or may be used to replace thefeatures of the other embodiments.

As used herein, the terms the terms “comprise,” “include,” “have” andany variations thereof, are intended to cover a non-exclusive inclusion,such that a process, method, article, or apparatus that comprises a listof elements is not necessarily limited to those elements, but mayinclude other elements not expressly listed or inherent to such process,method, article, or apparatus.

Further, in the disclosure the methods are not limited to a processperformed in temporal sequence according to the order described therein,instead, they can be executed in other temporal sequence, or be executedin parallel or separatively. That is, the executing orders describedabove should not be regarded as limiting the method thereto.

While some embodiments and examples have been disclosed above, it shouldbe noted that these embodiments and examples are only used to illustratethe present disclosure but not to limit the present disclosure. Variousmodifications, improvements and equivalents can be made by those skilledin the art without departing from the scope of the present disclosure.Such modifications, improvements and equivalents should also be regardedas being covered by the protection scope of the present disclosure.

The invention claimed is:
 1. An electronic device, comprising circuitryconfigured to: apply separate DRX configurations for a plurality ofcells with different attributes while applying a common DRXconfiguration for a group of cells with a common attribute; monitorphysical downlink control channels of the plurality of cells based onthe corresponding DRX configurations; receive a contention resolutionsuccess message on at least one of a primary cell and a secondary cellin the group of cells; start a common Contention Resolution Timer for acontention based random access procedure for the group of cells; andstop the common Contention Resolution Timer when the contentionresolution success message is received on any of the at least one of theprimary cell and the secondary cell.
 2. The electronic device accordingto claim 1, wherein the cells in the group of cells have similarcoverage and the cells in the plurality of cells have differentcoverages.
 3. The electronic device according to claim 1, wherein thecells in the group of cells are in same frequency band and the cells inthe plurality of cells are in different frequency bands.
 4. Theelectronic device according to claim 1, wherein the circuitry is furtherconfigured to start or reset an on Duration Timer and/or a DRXinactivity timer for the cells in the group of cells.
 5. The electronicdevice according to claim 1, wherein the circuitry is further configuredto configure common DRX parameters for the cells in the group of cells.6. The electronic device according to claim 5, wherein the circuitry isfurther configured to receive a signaling from a base station servingthe electronic device and configure a common on Duration Timer and/or acommon discontinuous reception inactivity timer based on the signaling.7. The electronic device according to claim 5, wherein the DRXparameters comprise at least one of on Duration Timer, DRX inactivitytimer, DRX Retransmission Timer, Long DRX Cycle and DRX Short Cycletimer and DRX Short Cycle.
 8. The electronic device according to claim1, wherein the electronic device is a user equipment and furthercomprises a transceiver which is configured to receive signals on thephysical downlink control channels of the plurality of cells based onthe corresponding DRX configurations.
 9. The electronic device accordingto claim 1, wherein the circuitry is configured to receive thecontention resolution success message on both of the primary cell andthe secondary cell.
 10. A method, comprising applying, using circuitry,separate DRX configurations for a plurality of cells with differentattributes while applying a common DRX configuration for a group ofcells with a common attribute; monitoring physical downlink controlchannels of the plurality of cells based on the corresponding DRXconfigurations; receiving a contention resolution success message on atleast one of a primary cell and a secondary cell in the group of cells;starting a common Contention Resolution Timer for a contention basedrandom access procedure for the group of cells; and stopping the commonContention Resolution Tinier when the contention resolution successmessage is received on any of the at least one of the primary cell andthe secondary cell.
 11. The method according to claim 10, wherein thecells in the group of cells have similar coverage and the cells in theplurality of cells have different coverages.
 12. The method according toclaim 10, wherein the cells in the group of cells are in the samefrequency band and the cells in the plurality of cells are in differentfrequency bands.
 13. The method according to claim 10, furthercomprising: starting or resetting an on Duration Timer and/or a DRXinactivity timer for the cells in the group of cells.
 14. The methodaccording to claim 10, further comprising: configuring common DRXparameters for the secondary cell and primary cell.
 15. The methodaccording to claim 14, further comprising: receiving a signaling fromthe base station and configure a common on Duration Timer and/or acommon discontinuous reception inactivity timer based on the signaling.16. The method according to claim 14, wherein the DRX parameterscomprise at least one of on Duration Timer, DRX inactivity timer, DRXRetransmission Timer, Long DRX Cycle and DRX Short Cycle timer and DRXShort Cycle.
 17. The method according to claim 10, further comprising:starting or resetting a DRX Inactivity Timer of a secondary cell whichis indicated in a carrier indicator field received via another cell. 18.The method according to claim 10, wherein the contention resolutionsuccess message is received on both of the primary cell and thesecondary cell.
 19. A non-transitory computer readable medium encodedwith computer-readable instructions thereon, the compute-readableinstructions, when executed by a computer, cause the computer to performa method comprising: applying separate DRX configurations for aplurality of cells with different attributes while applying a common DRXconfiguration for a group of cells with a common attribute; monitoringphysical downlink control channels of the plurality of cells based onthe corresponding DRX configurations; receiving a contention resolutionsuccess message on at least one of a primary cell and a secondary cellin the group of cells; starting a common Contention Resolution Timer fora contention based random access procedure for the group of cells; andstopping the common Contention Resolution Timer when the contentionresolution success message is received on any of the at least one of theprimary cell and the secondary cell.
 20. The non-transitory computerreadable medium according to claim 19, wherein the contention resolutionsuccess message is received on both of the primary cell and thesecondary cell.